System and method for communicating optical signals between a data service provider and subscribers

ABSTRACT

An optical fiber network can include an outdoor laser transceiver node that can be positioned in close proximity to the subscribers of an optical fiber network. The outdoor laser transceiver node does not require active cooling and heating devices that control the temperature surrounding the laser transceiver node. The laser transceiver node can adjust a subscriber&#39;s bandwidth on a subscription basis or on an as-needed basis. The laser transceiver node can also offer data bandwidth to the subscriber in preassigned increments. Additionally, the laser transceiver node lends itself to efficient upgrading that can be performed entirely on the network side. The laser transceiver node can also provide high speed symmetrical data transmission. Further, the laser transceiver node can utilize off the shelf hardware to generate optical signals such as Fabry-Perot (F-P) laser transmitters, distributed feed back lasers (DFB), or vertical cavity surface emitting lasers (VCSELs).

BACKGROUND OF THE INVENTION

[0001] The increasing reliance on communication networks to transmitmore complex data, such as voice and video traffic, is causing a veryhigh demand for bandwidth. To resolve this demand for bandwidth,communication networks are relying more upon optical fibers to transmitthis complex data. Conventional communication architectures that employcoaxial cables are slowly being replaced with communication networksthat comprise only fiber optic cables. One advantage that optical fibershave over coaxial cables is that a much greater amount of informationcan be carried on an optical fiber.

[0002] The Fiber-to-the-home (FTTH) optical network architecture hasbeen a dream of many data service providers because of theaforementioned capacity of optical fibers that enable the delivery ofany mix of high-speed services to businesses and consumers over highlyreliable networks. Related to FTTH is fiber to the business (FTTB). FTTHand FTTB architectures are desirable because of improved signal quality,lower maintenance, and longer life of the hardware involved with suchsystems. However, in the past, the cost of FTTH and FTTB architectureshave been considered prohibitive. But now, because of the high demandfor bandwidth and the current research and development of improvedoptical networks, FTTH and FTTB have become a reality.

[0003] One example of a FTTH architecture that has been introduced bythe industry is a passive optical network (PON). While the PONarchitecture does provide an all fiber network, it has many drawbacksthat make such a system impractical to implement. One drawback of thePON architecture is that too many optical cables must originate at thehead end or data service hub due to limitations in the number of timesan optical signal can be divided before the signal becomes too weak touse. Another drawback can be attributed to the passive nature of a PONnetwork. In other words, because there are no active signal sourcesdisposed between the data service hub and the subscriber, the maximumdistance that can be achieved between the data service hub and asubscriber usually falls within the range of 10 to 20 kilometers.

[0004] Another significant drawback of the PON architecture is the highcost of the equipment needed at the data service hub. For example, manyPON architectures support the full service access network (FSAN) whichuses the asynchronous transfer mode (ATM) protocol. To support thisprotocol, rather complex and expensive equipment is needed.

[0005] In addition to the high data service hub costs, conventional PONarchitectures do not lend themselves to efficient upgrades. That is,conventional or traditional PON architectures force physicalreconfiguration of the network by adding fiber and router ports in orderto increase the data speed of the network.

[0006] The data speeds in the downstream and upstream directions isanother drawback of the PON architecture. Conventional PON architecturestypically support up to 622 Megabit per second speeds in the downstreamdirection while only supporting maximum speeds of 155 Megabit per secondspeeds in the upstream direction. Such unbalanced communication speedsbetween the upstream and downstream communication directions isundesirable and is often referred to as asymmetrical bandwidth. Thisasymmetrical bandwidth places a low ceiling or low threshold for theamount of information that can be transferred from a subscriber to adata service hub. The assymetrical bandwidth is a result of the highcost of optical components required.

[0007] To overcome the asymmetrical bandwidth problem and the limiteddistance between the subscriber and the data service hub, a conventionalhybrid fiber-to-the-home (FTTH)/hybrid fiber-coax (HFC) architecture hasbeen proposed by the industry. HFC is currently the architecture ofchoice for many cable television systems. In this FTTH/HFC architecture,an active signal source is placed between the data service hub and thesubscriber. Typically, in this architecture, the active signal sourcecomprises a router. This conventional router has multiple data portsthat are designed to support individual subscribers. More specifically,the conventional router uses a single port for each respectivesubscriber. Connected to each data port of the router is an opticalfiber which, in turn, is connected to the subscriber. The connectivitybetween data ports and optical fibers with this conventional FTTH/HFCarchitecture yields a very fiber intensive last mile. It is noted thatthe terms, “last mile” and “first mile”, are both generic terms used todescribe the last portion of an optical network that connects tosubscribers.

[0008] In addition to a high number of optical cables originating fromthe router, the FTTH/HFC architecture requires radio frequency signalsto be propagated along traditional coaxial cables. Because of the use ofcoaxial cables, numerous radio frequency (RF) amplifiers are neededbetween the subscriber and the data service hub. For example, RFamplifiers are typically needed every one to three kilometers in acoaxial type system. The use of coaxial cables in the FTTH/HFCarchitecture adds to the overall cost of the system because two separateand distinct networks are present in such an architecture. In otherwords, the FTTH/HFC architecture has high maintenance costs because ofthe completely different waveguides (coaxial cable in combination withoptical fiber) in addition to the electrical and optical equipmentneeded to support such two distinct systems. Stated more simply, theFTTH/HFC architecture merely combines an optical network with anelectrical network where both networks run independently of one another.

[0009] Another drawback of the FTTH/HFC architecture is that the activesignal source between the data service hub and subscriber, usuallyreferred to as the router, requires a protected environment thatoccupies a significant amount of space. That is, the conventional routerof the FTTH/HFC architecture requires an environmental cabinet that mustmaintain the router and related equipment at an optimum temperature. Tomaintain this optimum temperature, the environmental cabinet willtypically include active temperature control devices for heating andcooling the cabinet.

[0010] Stated more simply, the conventional router of the FTTH/HFCarchitecture can only operate at standard room temperatures. Therefore,active cooling and heating units that consume power are needed tomaintain such an operating temperature in all types of geographic areasand in all types of weather.

[0011] Unlike the FTTH/HFC architecture that employs two separatecommunication networks, another conventional hybrid fiber coax (HFC)architecture employs an active signal source between the data servicehub and the subscriber that does not require a temperature controlledenvironmental cabinet. However, this active signal source disposedbetween the subscriber and the data service hub merely provides opticalto electrical conversion of information signals. That is, the activesignal source disposed between a subscriber and a data service hub inthe HFC architecture converts downstream optical signals into electricalsignals and upstream electrical signals into optical signals. Theconventional HFC architecture relies upon coaxial cable to support allsignals in the last mile or so of the HFC network. Therefore, similar tothe FTTH/HFC architecture, the conventional HFC architecture alsorequires numerous RF amplifiers on the coaxial cable side of thenetwork.

[0012] Another drawback of the conventional HFC architecture exists atthe data service hub where numerous communication devices are needed tosupport the data signals propagating along the optical fibers betweenthe active signal source and the data service hub. For example, theconventional HFC architecture typically supports telephony service byusing equipment known generically as a host digital terminal (HDT). TheHDT can include RF interfaces on the cable side, and interfaces toeither a telephone switch or to a cable carrying signals to a switch onanother side.

[0013] Further, the data service hub of a conventional HFC architecturecan further include a cable modem termination system (CMTS). This systemprovides low level formatting and transmission functions for the datatransmitted between the data service hub and the subscriber. The CMTSsystem can operate by-directionally, meaning that it can send signalsboth downstream to subscribers and receive signals sent upstream fromsubscribers.

[0014] In addition to a CMTS, the conventional HFC architecture at thedata service hub typically includes several modulators that can compriseminiature television transmitters. Each modulator can convert videosignals received from satellites to an assigned channel (frequency) fortransmission to subscribers. In addition to the modulators, a signalprocessor and other devices are used to collect the entire suite oftelevision signals to be sent to subscribers. Typically, in aconventional HFC architecture, there can be 78 or more such modulatorsor processors with their supporting equipment to service the analog TVtier. Additionally, similar equipment to serve the digital video tier isoften used.

[0015] Another drawback of the conventional HFC architecture flows fromthe use of the CMTS. Similar to the passive optical network (PON)discussed above, the CMTS cannot support symmetrical bandwidth. That is,a bandwidth of the conventional HFC architecture is typicallyasymmetrical because of the use of the data over cable service interfacespecification (DOCSIS). The nature of the DOCSIS standard is that itlimits the upstream bandwidth available to subscribers. This can be adirect result of the limited upstream bandwidth available in an HFCplant. Such a property is undesirable for subscribers who need totransmit more complex data for bandwidth intensive services such as homeservers or the exchange of audio files over the Internet.

[0016] In another variation of the conventional HFC architecture, theCMTS can be part of the active signal source disposed between thesubscriber and the data service hub. While this variation of theconventional HFC architecture enables the active signal source toperform some processing, the output of the active signal source in thisarchitecture is still radio frequency energy and is propagated alongcoaxial cables.

[0017] Accordingly, there is a need in the art for a system and methodfor communicating optical signals between a data service provider and asubscriber that eliminates the use of coaxial cables and the relatedhardware and software necessary to support the data signals propagatingalong the coaxial cables. There is also a need in the art for a systemand method for communicating optical signals between a data serviceprovider and a subscriber that supports high speed symmetrical datatransmission. In other words, there is a need in the art for an allfiber optical network and method that can propagate the same bit ratedownstream and upstream to/from a network subscriber. Further, there isalso a need in the art for an optical network system and method that canservice a large number of subscribers while reducing the number ofconnections at the data service hub.

[0018] There is also a need in the art for an active signal source thatcan be disposed between a data service hub and a subscriber that can bedesigned to withstand outdoor environmental conditions and that can bedesigned to hang on a strand or fit in a pedestal similar toconventional cable TV equipment that is placed within a last mile of acommunications network. A further need exists in the art for a systemand method for receiving at least one gigabit or faster Ethernetcommunications in optical form from a data service hub and partition orapportion this optical bandwidth into distribution groups of apredetermined number. There is a further need in the art for a systemand method that can allocate additional or reduced bandwidth based uponthe demand of one or more subscribers on an optical network. Anotherneed exists in the art for an optical network system that lends itselfto efficient upgrading that can be performed entirely on the networkside. In other words, there is a need in the art for an optical networksystem that allows upgrades to hardware to take place in locationsbetween and within a data service hub and an active signal sourcedisposed between the data service hub and a subscriber.

SUMMARY OF THE INVENTION

[0019] The present invention is generally drawn to a system and methodfor efficient propagation of data and broadcast signals over an opticalfiber network. More specifically, the present invention is generallydrawn to an optical network architecture that can include an outdoorlaser transceiver, or processing node, that can be positioned in closeproximity to the subscribers of an optical fiber network. For example,the outdoor laser transceiver node can be designed to withstand outdoorenvironmental conditions and can be designed to hang on a strand or fitin a pedestal similar to conventional cable TV equipment that is placedwithin “the last mile” of a network.

[0020] Unlike the conventional routers disposed between the subscriberoptical interface and data service hub, the outdoor laser transceivernode does not require active cooling and heating devices that controlthe temperature surrounding the laser transceiver node. Further, thelaser transceiver node can operate over a wide temperature range.Because the laser transceiver node does not require active temperaturecontrolling devices, the laser transceiver node lends itself to acompact electronic packaging volume that is typically smaller than theenvironmental enclosures of conventional routers.

[0021] In contrast to conventional electronic cable TV equipment orconventional optical processing nodes, the laser transceiver node canreceive at least one gigabit or faster Ethernet communications inoptical form from the data service hub and partition or apportion thisoptical bandwidth into distribution groups of a predetermined number. Inone exemplary embodiment, the laser transceiver node can partition theoptical bandwidth into distribution groups comprising at least sixgroups of at least sixteen subscribers.

[0022] Using an appropriate protocol, the laser transceiver node canallocate additional or reduced bandwidth based upon the demand of one ormore subscribers. That is, the laser transceiver node can adjust asubscriber's bandwidth on a subscription basis or on an as-needed basis.The laser transceiver node can offer data bandwidth to the subscriber inpreassigned increments. For example, the laser transceiver node canoffer a particular subscriber or groups of subscribers bandwidth inunits of 1, 2, 5, 10, 20, 50, 100, 200, and 450 Megabits per second(Mb/s).

[0023] In addition to offering bandwidth in preassigned increments, thelaser transceiver node lends itself to efficient upgrading that can beperformed entirely on the network side. In other words, upgrades to thehardware forming the laser transceiver node can take place in locationsbetween and within a data service hub (such as a headend) and the lasertransceiver node themselves. This means that the subscriber side of thenetwork can be left entirely intact during an upgrade to the lasertransceiver node or data service hub or both.

[0024] The laser transceiver node can also provide high speedsymmetrical data transmission. In other words, the laser transceivernode can propagate the same bit rates downstream and upstream from anetwork subscriber. Further, the laser transceiver node can also serve alarger number of subscribers while reducing the number of connections atthe data service hub.

[0025] The flexibility and diversity of the laser transceiver node canbe attributed to at least a few components. The laser transceiver nodecan comprise an optical tap routing device that is coupled to one ormore tap multiplexers. The optical tap routing device can manage theinterface with the data service hub optical signals and can route ordivide or apportion the data service hub signals according to individualtap multiplexers that modulate laser transmitters to generate opticalsignals for specific optical taps. That is, unlike conventional routerswhich assign single ports to respective individual subscribers, theoptical tap routing device can assign multiple subscribers to a singleport. More specifically, each tap multiplexer connected to a port of theoptical tap routing device can service groups of subscribers. Theindividual tap multiplexers can modulate laser transmitters to supplydownstream optical signals to preassigned groups of subscribers coupledto optical taps. From the optical taps, subscribers can receive thedownstream optical signals with subscriber optical interfaces.

[0026] The optical tap routing device can determine which tapmultiplexer is to receive a downstream electrical signal, or identifywhich of the plurality of optical taps originated an upstream signal.The optical tap routing device can also format data and implement theprotocol required to send and receive data from each individualsubscriber connected to a respective optical tap (as will be discussedbelow). The optical tap routing device can comprise a computer or ahardwired apparatus that executes a program defining a protocol forcommunications with groups of subscribers assigned to single ports. Thesingle ports are connected to respective tap multiplexers (discussed infurther detail below).

[0027] The laser transceiver node further comprises off-the-shelfhardware to generate optical signals. For example, the laser transceivernode can comprise one or more Fabry-Perot (F-P) laser transmitters,distributed feed back lasers (DFBs), or vertical cavity surface emittinglasers (VCSELs). The laser transceiver node can also supportunidirectional optical signals originating from the data service hub.The laser transceiver node can combine the unidirectional opticalsignals with downstream optical signals so that a single opticalwaveguide can connect the laser transceiver node to a respectivesubscriber. The unidirectional optical signals can comprise broadcastvideo or other similar RF modulated optical signals.

[0028] The laser transceiver node is but one part of the presentinvention. The present invention also comprises an efficient coupler,referred to as an optical tap, between the laser transceiver node and arespective subscriber optical interface. The optical tap can divideoptical signals between a plurality of subscribers and can be simple inits design. For example, each optical tap can comprise an opticalsplitter that may feed one or more subscribers. Optical taps can becascaded or they can be connected in a star architecture from the lasertransceiver node. The optical tap can also route signals to otheroptical taps that are downstream relative to a respective optical tap.The optical tap can also connect to a small number of optical waveguidesso that high concentrations of optical waveguides are not present at anyparticular laser transceiver node. In other words, the optical tap canconnect to a predetermined number of optical waveguides at a pointremote from the laser transceiver node so that high concentrations ofoptical waveguides at the laser transceiver node can be avoided.

[0029] As noted above, the optical tap and laser transceiver node areparts of the present invention. The present invention can include asystem that comprises the optical tap, the laser transceiver node, adata service hub, a subscriber optical interface, and optical waveguidesconnected between the optical taps and laser transceiver node.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030]FIG. 1 is a functional block diagram of some core components of anexemplary optical network architecture according to the presentinvention.

[0031]FIG. 2 is a functional block diagram illustrating an exemplaryoptical network architecture for the present invention.

[0032]FIG. 3 is a functional block diagram illustrating an exemplarydata service hub of the present invention.

[0033]FIG. 4 is a functional block diagram illustrating an exemplaryoutdoor laser transceiver node according to the present invention.

[0034]FIG. 5 is a functional block diagram illustrating an optical tapconnected to a subscriber interface by a single optical waveguideaccording to one exemplary embodiment of the present invention.

[0035]FIG. 6 is a functional block diagram illustrating an exemplarydata service hub according to an alternative exemplary embodiment of thepresent invention where upstream optical signals and downstream opticalsignals are propagated along separate optical waveguides.

[0036]FIG. 7 is a functional block diagram illustrating an exemplaryoutdoor laser transceiver node that can accept upstream and downstreamoptical signals that are propagated along separate optical waveguides inaddition to unidirectional signals that can be mixed with the downstreamoptical signals.

[0037]FIG. 8 is a functional block diagram illustrating yet anotherexemplary outdoor laser transceiver node that can accept optical signalspropagating in separate upstream and downstream optical waveguides inaddition to multiple optical waveguides that propagate unidirectionalsignals.

[0038]FIG. 9 is a functional block diagram illustrating anotherexemplary embodiment of a data service hub in which unidirectionalsignals such as video or RF signals are combined with downstream opticalsignals.

[0039]FIG. 10 is a functional block diagram illustrating anotherexemplary outdoor laser transceiver node that can process a combineddownstream signal that comprises downstream optical signals in additionto unidirectional signals like RF transmissions or video data.

[0040]FIG. 11 is a functional block diagram illustrating anotherexemplary outdoor laser transceiver node that employs dual transceiversbetween tap multiplexers and respective groups of subscribers.

[0041]FIG. 12 is a functional block diagram illustrating anotherexemplary outdoor laser transceiver node that includes optical tapsdisposed within the laser transceiver node itself.

[0042]FIG. 13 is a logic flow diagram illustrating an exemplary methodfor processing unidirectional and bidirectional optical signals with alaser transceiver node of the present invention.

[0043]FIG. 14 is a logic flow diagram illustrating an exemplary processfor handling downstream optical signals with a laser transceiver nodeaccording to the present invention.

[0044]FIG. 15 is a logic flow diagram illustrating an exemplary processfor handling upstream optical signals with an exemplary lasertransceiver node according to the present invention.

[0045]FIG. 16 is a logic flow diagram illustrating the processing ofunidirectional and bidirectional optical signals with an optical tapaccording to the present invention.

[0046]FIG. 17 is a logic flow diagram illustrating the processing ofunidirectional optical signals and bidirectional optical signals with asubscriber interface according to the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0047] The present invention may be embodied in hardware or software ora combination thereof disposed within an optical network. The presentinvention can comprise a laser transceiver node disposed between a dataservice hub and a subscriber that can allocate additional or reducedbandwidth based upon the demand of one or more subscribers. The presentinvention can support one gigabit or faster Ethernet communications inoptical form to and from the data service hub and partition or apportionthis optical bandwidth into distribution groups of a predeterminednumber. The present invention allows bandwidth to be offered tosubscribers in preassigned increments. The flexibility and diversity ofthe present invention can be attributed to a few components.

[0048] The laser transceiver node of the present invention can comprisean optical tap routing device that is coupled to one or more tapmultiplexers. The optical tap routing device can assign multiplesubscribers to a single port that receives downstream optical signalsfrom a data service hub. The laser transceiver node of the presentinvention can comprise off-the-shelf hardware to generate opticalsignals. For example, the laser transceiver node of the presentinvention can comprise one or more Fabry-Perot (F-P) lasers, distributedfeedback lasers, or Vertical Cavity Surface Emitting Lasers (VCSELs) inthe transmitters. The present invention can also comprise efficientcouplers, such as optical taps, between the laser transceiver node and arespective subscriber optical interface.

[0049] The optical tap can divide optical signals among a plurality ofsubscribers and can be simple in its design. The optical tap can connectto a limited number of optical waveguides at a point remote from thelaser transceiver node so that high concentrations of optical waveguidesat the laser transceiver node can be avoided. In another exemplaryembodiment, the optical tap can be disposed within the laser transceivernode of the present invention.

[0050] Referring now to the drawings, in which like numerals representlike elements throughout the several Figures, aspects of the presentinvention and the illustrative operating environment will be described.

[0051]FIG. 1 is a functional block diagram illustrating an exemplaryoptical network architecture 100 according to the present invention. Theexemplary optical network architecture 100 comprises a data service hub110 that is connected to outdoor laser transceiver nodes 120. The lasertransceiver nodes 120, in turn, are connected to an optical taps 130.The optical taps 130 can be connected to a plurality of subscriberoptical interfaces 140. Between respective components of the exemplaryoptical network architecture 100 are optical waveguides such as opticalwaveguides 150, 160, 170, and 180. The optical waveguides 150-180 areillustrated by arrows where the arrowheads of the arrows illustrateexemplary directions of data flow between respective components of theillustrative and exemplary optical network architecture 100. While onlyan individual laser transceiver node 120, an individual optical tap 130,and an individual subscriber optical interface 140 are illustrated inFIG. 1, as will become apparent from FIG. 2 and its correspondingdescription, a plurality of laser transceiver nodes 120, optical taps130, and subscriber optical interfaces 140 can be employed withoutdeparting from the scope and spirit of the present invention. Typically,in many of the exemplary embodiments of the present invention, multiplesubscriber optical interfaces 140 are connected to one or more opticaltaps 130.

[0052] The outdoor laser transceiver node 120 can allocate additional orreduced bandwidth based upon the demand of one or more subscribers thatuse the subscriber optical interfaces 140. The outdoor laser transceivernode 120 can be designed to withstand outdoor environmental conditionsand can be designed to hang on a strand or fit in a pedestal or “hardhole.” The outdoor laser transceiver node can operate in a temperaturerange between minus 40 degrees Celsius to plus 60 degrees Celsius. Thelaser transceiver node 120 can operate in this temperature range byusing passive cooling devices that do not consume power.

[0053] Unlike the conventional routers disposed between the subscriberoptical interface 140 and data service hub 110, the outdoor lasertransceiver node 120 does not require active cooling and heating devicesthat control the temperature surrounding the laser transceiver node 120.The present invention attempts to place more of the decision-makingelectronics at the data service hub 110 instead of the laser transceivernode 120. Typically, the decision-making electronics are larger in sizeand produce more heat than the electronics placed in the lasertransceiver node of the present invention. Because the laser transceivernode 120 does not require active temperature controlling devices, thelaser transceiver node 120 lends itself to a compact electronicpackaging volume that is typically smaller than the environmentalenclosures of conventional routers. Further details of the componentsthat make up the laser transceiver node 120 will be discussed in furtherdetail below with respect to FIGS. 4, 7, 8, 10, 11, and 12.

[0054] In one exemplary embodiment of the present invention, three trunkoptical waveguides 160, 170, and 180 (that can comprise optical fibers)can conduct optical signals from the data service hub 110 to the outdoorlaser transceiver node 120. It is noted that the term “opticalwaveguide” used in the present application can apply to optical fibers,planar light guide circuits, and fiber optic pigtails and other likeoptical waveguides.

[0055] A first optical waveguide 160 can carry broadcast video and othersignals. The signals can be carried in a traditional cable televisionformat wherein the broadcast signals are modulated onto carriers, whichin turn, modulate an optical transmitter (not shown) in the data servicehub 110. A second optical waveguide 170 can carry downstream targetedservices such as data and telephone services to be delivered to one ormore subscriber optical interfaces 140. In addition to carryingsubscriber-specific optical signals, the second optical waveguide 170can also propagate internet protocol broadcast packets, as is understoodby those skilled in the art.

[0056] In one exemplary embodiment, a third optical waveguide 180 cantransport data signals upstream from the outdoor laser transceiver node120 to the data service hub 110. The optical signals propagated alongthe third optical waveguide 180 can also comprise data and telephoneservices received from one or more subscribers. Similar to the secondoptical waveguide 170, the third optical waveguide 180 can also carry IPbroadcast packets, as is understood by those skilled in the art.

[0057] The third or upstream optical waveguide 180 is illustrated withdashed lines to indicate that it is merely an option or part of oneexemplary embodiment according to the present invention. In other words,the third optical waveguide 180 can be removed. In another exemplaryembodiment, the second optical waveguide 170 propagates optical signalsin both the upstream and downstream directions as is illustrated by thedouble arrows depicting the second optical waveguide 170. In such anexemplary embodiment where the second optical waveguide 170 propagatesbidirectional optical signals, only two optical waveguides 160, 170would be needed to support the optical signals propagating between thedata server's hub 110 in the outdoor laser transceiver node 120. Inanother exemplary embodiment (not shown), a single optical waveguide canbe the only link between the data service hub 110 and the lasertransceiver node 120. In such a single optical waveguide embodiment,three different wavelengths can be used for the upstream and downstreamsignals. Alternatively, bi-directional data could be modulated on onewavelength.

[0058] In one exemplary embodiment, the optical tap 130 can comprise an8-way optical splitter. This means that the optical tap 130 comprisingan 8-way optical splitter can divide downstream optical signals eightways to serve eight different subscriber optical interfaces 140. In theupstream direction, the optical tap 130 can combine the optical signalsreceived from the eight subscriber optical interfaces 140.

[0059] In another exemplary embodiment, the optical tap 130 can comprisea 4-way splitter to service four subscriber optical interfaces 140. Yetin another exemplary embodiment, the optical tap 130 can furthercomprise a 4-way splitter that is also a pass-through tap meaning that aportion of the optical signal received at the optical tap 130 can beextracted to serve the 4-way splitter contained therein while theremaining optical energy is propagated further downstream to anotheroptical tap or another subscriber optical interface 140. The presentinvention is not limited to 4-way and 8-way optical splitters. Otheroptical taps having fewer or more than 4-way or 8-way splits are notbeyond the scope of the present invention.

[0060] Referring now to FIG. 2, this Figure is a functional blockdiagram illustrating an exemplary optical network architecture 100 thatfurther includes subscriber groupings 200 that correspond with arespective outdoor laser transceiver node 120. FIG. 2 illustrates thediversity of the exemplary optical network architecture 100 where anumber of optical waveguides 150 connected between the outdoor lasertransceiver node 120 and the optical taps 130 is minimized. FIG. 2 alsoillustrates the diversity of subscriber groupings 200 that can beachieved with the optical tap 130.

[0061] Each optical tap 130 can comprise an optical splitter. Theoptical tap 130 allows multiple subscriber optical interfaces 140 to becoupled to a single optical waveguide 150 that is connected to theoutdoor laser transceiver node 120. In one exemplary embodiment, sixoptical fibers 150 are designed to be connected to the outdoor lasertransceiver node 120. Through the use of the optical taps 130, sixteensubscribers can be assigned to each of the six optical fibers 150 thatare connected to the outdoor laser transceiver node 120.

[0062] In another exemplary embodiment, twelve optical fibers 150 can beconnected to the outdoor laser transceiver node 120 while eightsubscriber optical interfaces 140 are assigned to each of the twelveoptical fibers 150. Those skilled in the art will appreciate that thenumber of subscriber optical interfaces 140 assigned to a particularwaveguide 150 that is connected between the outdoor laser transceivernode 120 and a subscriber optical interface 140 (by way of the opticaltap 130) can be varied or changed without departing from the scope andspirit of the present invention. Further, those skilled in the artrecognize that the actual number of subscriber optical interfaces 140assigned to the particular fiber optic cable is dependent upon theamount of power available on a particular optical fiber 150.

[0063] As depicted in subscriber grouping 200, many configurations forsupplying communication services to subscribers are possible. Forexample, while optical tap 130 _(A) can connect subscriber opticalinterfaces 140 _(A1) through subscriber optical interface 140 _(AN) tothe outdoor laser transmitter node 120, optical tap 130 _(A) can alsoconnect other optical taps 130 such as optical tap 130 _(AN) to thelaser transceiver node 120. The combinations of optical taps 130 withother optical taps 130 in addition to combinations of optical taps 130with subscriber optical interfaces 140 are limitless. With the opticaltaps 130, concentrations of distribution optical waveguides 150 at thelaser transceiver node 120 can be reduced. Additionally, the totalamount of fiber needed to service a subscriber grouping 200 can also bereduced.

[0064] With the active laser transceiver node 120 of the presentinvention, the distance between the laser transceiver node 120 and thedata service hub 110 can comprise a range between 0 and 80 kilometers.However, the present invention is not limited to this range. Thoseskilled in the art will appreciate that this range can be expanded byselecting various off-the-shelf components that make up several of thedevices of the present system.

[0065] Those skilled in the art will appreciate that otherconfigurations of the optical waveguides disposed between the dataservice hub 110 and outdoor laser transceiver node 120 are not beyondthe scope of the present invention. Because of the bi-directionalcapability of optical waveguides, variations in the number anddirectional flow of the optical waveguides disposed between the dataservice hub 110 and the outdoor laser transceiver node 120 can be madewithout departing from the scope and spirit of the present invention.

[0066] Referring now to FIG. 3, this functional block diagramillustrates an exemplary data service hub 110 of the present invention.The exemplary data service hub 110 illustrated in FIG. 3 is designed fora two trunk optical waveguide system. That is, this data service hub 110of FIG. 3 is designed to send and receive optical signals to and fromthe outdoor laser transceiver node 120 along the first optical waveguide160 and the second optical waveguide 170. With this exemplaryembodiment, the second optical waveguide 170 supports bidirectional dataflow. In this way, the third optical waveguide 180 discussed above isnot needed.

[0067] The data service hub 110 can comprise one or more modulators 310,315 that are designed to support television broadcast services. The oneor more modulators 310, 315 can be analog or digital type modulators. Inone exemplary embodiment, there can be at least 78 modulators present inthe data service hub 110. Those skilled in the art will appreciate thatthe number of modulators 310, 315 can be varied without departing fromthe scope and spirit of the present invention.

[0068] The signals from the modulators 310, 315 are combined in acombiner 320 where they are supplied to an optical transmitter 325 wherethe radio frequency signals generated by the modulators 310, 315 areconverted into optical form.

[0069] The optical transmitter 325 can comprise one of Fabry-Perot (F-P)Laser Transmitters, distributed feedback lasers (DFBs), or VerticalCavity Surface Emitting Lasers (VCSELs). However, other types of opticaltransmitters are possible and are not beyond the scope of the presentinvention. With the aforementioned optical transmitters 325, the dataservice hub 110 lends itself to efficient upgrading by usingoff-the-shelf hardware to generate optical signals.

[0070] The optical signals generated by the optical transmitter (oftenreferred to as the unidirectional optical signals) are propagated toamplifier 330 such as an Erbium Doped Fiber Amplifier (EDFA) where theunidirectional optical signals are amplified. The amplifiedunidirectional optical signals are then propagated out of the dataservice hub 110 via a unidirectional signal output port 335 which isconnected to one or more first optical waveguides 160.

[0071] The unidirectional signal output port 335 is connected to one ormore first optical waveguides 160 that support unidirectional opticalsignals originating from the data service hub 110 to a respective lasertransceiver node 120. The data service hub 110 illustrated in FIG. 3 canfurther comprise an Internet router 340. The data service hub 110 canfurther comprise a telephone switch 345 that supports telephony serviceto the subscribers of the optical network system 100. However, othertelephony service such as Internet Protocol telephony can be supportedby the data service hub 110. If only Internet Protocol telephony issupported by the data service hub 110, then it is apparent to thoseskilled in the art that the telephone switch 345 could be eliminated infavor of lower cost VoIP equipment. For example, in another exemplaryembodiment (not shown), the telephone switch 345 could be substitutedwith other telephone interface devices such as a soft switch andgateway. But if the telephone switch 345 is needed, it may be locatedremotely from the data service hub 110 and can be connected through anyof several conventional means of interconnection.

[0072] The data service hub 110 can further comprise a logic interface350 that is connected to a laser transceiver node routing device 355.The logic interface 350 can comprise a Voice over Internet Protocol(VoIP) gateway when required to support such a service. The lasertransceiver node routing device 355 can comprise a conventional routerthat supports an interface protocol for communicating with one or morelaser transceiver nodes 120. This interface protocol can comprise one ofgigabit or faster Ethernet, Internet Protocol (IP) or SONET protocols.However, the present invention is not limited to these protocols. Otherprotocols can be used without departing from the scope and spirit of thepresent invention.

[0073] The logic interface 350 and laser transceiver node routing device355 can read packet headers originating from the laser transceiver nodes120 and the internet router 340. The logic interface 350 can alsotranslate interfaces with the telephone switch 345. After reading thepacket headers, the logic interface 350 and laser transceiver noderouting device 355 can determine where to send the packets ofinformation.

[0074] The laser transceiver node routing device 355 can supplydownstream data signals to respective optical transmitters 325. The datasignals converted by the optical transmitters 325 can then be propagatedto a bi-directional splitter 360. The optical signals sent from theoptical transmitter 325 into the bi-directional splitter 360 can then bepropagated towards a bi-directional data input/output port 365 that isconnected to a second optical waveguide 170 that supports bi-directionaloptical data signals between the data service hub 110 and a respectivelaser transceiver node 120. Upstream optical signals received from arespective laser transceiver node 120 can be fed into the bi-directionaldata input/output port 365 where the optical signals are then forwardedto the bi-directional splitter 360. From the bi-directional splitter360, respective optical receivers 370 can convert the upstream opticalsignals into the electrical domain. The upstream electrical signalsgenerated by respective optical receivers 370 are then fed into thelaser transceiver node routing device 355. Each optical receiver 370 cancomprise one or more photoreceptors or photodiodes that convert opticalsignals into electrical signals.

[0075] When distances between the data service hub 110 and respectivelaser transceiver nodes 120 are modest, the optical transmitters 325 canpropagate optical signals at 1310 nm. But where distances between thedata service hub 110 and the laser transceiver node are more extreme,the optical transmitters 325 can propagate the optical signals atwavelengths of 1550 nm with or without appropriate amplificationdevices.

[0076] Those skilled in the art will appreciate that the selection ofoptical transmitters 325 for each circuit may be optimized for theoptical path lengths needed between the data service hub 110 and theoutdoor laser transceiver node 120. Further, those skilled in the artwill appreciate that the wavelengths discussed are practical but areonly illustrative in nature. In some scenarios, it may be possible touse communication windows at 1310 and 1550 nm in different ways withoutdeparting from the scope and spirit of the present invention. Further,the present invention is not limited to a 1310 and 1550 nm wavelengthregions. Those skilled in the art will appreciate that smaller or largerwavelengths for the optical signals are not beyond the scope and spiritof the present invention.

[0077] Referring now to FIG. 4, this Figure illustrates a functionalblock diagram of an exemplary outdoor laser transceiver node 120 of thepresent invention. In this exemplary embodiment, the laser transceivernode 120 can comprise a unidirectional optical signal input port 405that can receive optical signals propagated from the data service hub110 that are propagated along a first optical waveguide 160. The opticalsignals received at the unidirectional optical signal input port 405 cancomprise broadcast video data. The optical signals received at the inputport 405 are propagated to an amplifier 410 such as an Erbium DopedFiber Amplifier (EDFA) in which the optical signals are amplified. Theamplified optical signals are then propagated to a splitter 415 thatdivides the broadcast video optical signals among diplexers 420 that aredesigned to forward optical signals to predetermined subscriber groups200.

[0078] The laser transceiver node 120 can further comprise abi-directional optical signal input/output port 425 that connects thelaser transceiver node 120 to a second optical waveguide 170 thatsupports bi-directional data flow between the data service hub 110 andlaser transceiver node 120. Downstream optical signals flow through thebidirectional optical signal input/output port 425 to an opticalwaveguide transceiver 430 that converts downstream optical signals intothe electrical domain. The optical waveguide transceiver furtherconverts upstream electrical signals into the optical domain. Theoptical waveguide transceiver 430 can comprise an optical/electricalconverter and an electrical/optical converter.

[0079] Downstream and upstream electrical signals are communicatedbetween the optical waveguide transceiver 430 and an optical tap routingdevice 435. The optical tap routing device 435 can manage the interfacewith the data service hub optical signals and can route or divide orapportion the data service hub signals according to individual tapmultiplexers 440 that communicate optical signals with one or moreoptical taps 130 and ultimately one or more subscriber opticalinterfaces 140. It is noted that tap multiplexers 440 operate in theelectrical domain to modulate laser transmitters in order to generateoptical signals that are assigned to groups of subscribers coupled toone or more optical taps.

[0080] Optical tap routing device 435 is notified of available upstreamdata packets as they arrive, by each tap multiplexer 440. The opticaltap routing device is connected to each tap multiplexer 440 to receivethese upstream data packets. The optical tap routing device 435 relaysthe packets to the data service hub 110 via the optical waveguidetransceiver 430. The optical tap routing device 435 can build a lookuptable from these upstream data packets coming to it from all tapmultiplexers 440 (or ports), by reading the source IP address of eachpacket, and associating it with the tap multiplexer 440 through which itcame. This lookup table can then used to route packets in the downstreampath. As each packet comes in from the optical waveguide transceiver430, the optical tap routing device looks at the destination IP address(which is the same as the source IP address for the upstream packets).From the lookup table the optical tap routing device can determine whichport is connected to that IP address, so it sends the packet to thatport. This can be described as a normal layer 3 router function as isunderstood by those skilled in the art.

[0081] The optical tap routing device 435 can assign multiplesubscribers to a single port. More specifically, the optical tap routingdevice 435 can service groups of subscribers with correspondingrespective, single ports. The optical taps 130 coupled to respective tapmultiplexers 440 can supply downstream optical signals to preassignedgroups of subscribers who receive the downstream optical signals withthe subscriber optical interfaces 140.

[0082] In other words, the optical tap routing device 435 can determinewhich tap multiplexers 440 is to receive a downstream electrical signal,or identify which of a plurality of optical taps 130 propagated anupstream optical signal (that is converted to an electrical signal). Theoptical tap routing device 435 can format data and implement theprotocol required to send and receive data from each individualsubscriber connected to a respective optical tap 130. The optical taprouting device 435 can comprise a computer or a hardwired apparatus thatexecutes a program defining a protocol for communications with groups ofsubscribers assigned to individual ports. One exemplary embodiment ofthe program defining the protocol is discussed in copending and commonlyassigned provisional patent application entitled, “Protocol to ProvideVoice and Data Services via Fiber Optic Cable,” filed on Oct. 27, 2000and assigned U.S. application Ser. No. 60/243,978, the entire contentsof which are incorporated by reference. Another exemplary embodiment ofthe program defining the protocol is discussed in copending and commonlyassigned provisional patent application entitled, “Protocol to ProvideVoice and Data Services via Fiber Optic Cable-Part 2,” filed on May 7,2001 and assigned U.S. application Ser. No. 60/289,112, the entirecontents of which are incorporated by reference.

[0083] The single ports of the optical tap routing device are connectedto respective tap multiplexers 440. With the optical tap routing device435, the laser transceiver node 120 can adjust a subscriber's bandwidthon a subscription basis or on an as-needed or demand basis. The lasertransceiver node 120 via the optical tap routing device 435 can offerdata bandwidth to subscribers in pre-assigned increments. For example,the laser transceiver node 120 via the optical tap routing device 435can offer a particular subscriber or groups of subscribers bandwidth inunits of 1, 2, 5, 10, 20, 50, 100, 200, and 450 Megabits per second(Mb/s). Those skilled in the art will appreciate that other subscriberbandwidth units are not beyond the scope of the present invention.

[0084] Electrical signals are communicated between the optical taprouting device 435 and respective tap multiplexers 440. The tapmultiplexers 440 propagate optical signals to and from various groupingsof subscribers. Each tap multiplexer 440 is connected to a respectiveoptical transmitter 325. As noted above, each optical transmitter 325can comprise one of a Fabry-Perot (F-P) laser, a distributed feedbacklaser (DFB), or a Vertical Cavity Surface Emitting Laser (VCSEL). Theoptical transmitters produce the downstream optical signals that arepropagated towards the subscriber optical interfaces 140. Each tapmultiplexer 440 is also coupled to an optical receiver 370. Each opticalreceiver 370, as noted above, can comprise photoreceptors orphotodiodes. Since the optical transmitters 325 and optical receivers370 can comprise off-the-shelf hardware to generate and receiverespective optical signals, the laser transceiver node 120 lends itselfto efficient upgrading and maintenance to provide significantlyincreased data rates.

[0085] Each optical transmitter 325 and each optical receiver 370 areconnected to a respective bidirectional splitter 360. Eachbi-directional splitter 360 in turn is connected to a diplexer 420 whichcombines the unidirectional optical signals received from the splitter415 with the downstream optical signals received from respective opticalreceivers 370. In this way, broadcast video services as well as dataservices can be supplied with a single optical waveguide such as adistribution optical waveguide 150 as illustrated in FIG. 2. In otherwords, optical signals can be coupled from each respective diplexer 420to a combined signal input/output port 445 that is connected to arespective distribution optical waveguide 150.

[0086] Unlike the conventional art, the laser transceiver node 120 doesnot employ a conventional router. The components of the lasertransceiver node 120 can be disposed within a compact electronicpackaging volume. For example, the laser transceiver node 120 can bedesigned to hang on a strand or fit in a pedestal similar toconventional cable TV equipment that is placed within the “last,” mileor subscriber proximate portions of a network. It is noted that theterm, “last mile,” is a generic term often used to describe the lastportion of an optical network that connects to subscribers.

[0087] Also because the optical tap routing device 435 is not aconventional router, it does not require active temperature controllingdevices to maintain the operating environment at a specific temperature.In other words, the laser transceiver node 120 can operate in atemperature range between minus 40 degrees Celsius to 60 degrees Celsiusin one exemplary embodiment.

[0088] While the laser transceiver node 120 does not comprise activetemperature controlling devices that consume power to maintaintemperature of the laser transceiver node 120 at a single temperature,the laser transceiver node 120 can comprise one or more passivetemperature controlling devices 450 that do not consume power. Thepassive temperature controlling devices 450 can comprise one or moreheat sinks or heat pipes that remove heat from the laser transceivernode 120. Those skilled in the art will appreciate that the presentinvention is not limited to these exemplary passive temperaturecontrolling devices. Further, those skilled in the art will alsoappreciate the present invention is not limited to the exemplaryoperating temperature range disclosed. With appropriate passivetemperature controlling devices 450, the operating temperature range ofthe laser transceiver node 120 can be reduced or expanded.

[0089] In addition to the laser transceiver node's 120 ability towithstand harsh outdoor environmental conditions, the laser transceivernode 120 can also provide high speed symmetrical data transmissions. Inother words, the laser transceiver node 120 can propagate the same bitrates downstream and upstream to and from a network subscriber. This isyet another advantage over conventional networks, which typically cannotsupport symmetrical data transmissions as discussed in the backgroundsection above. Further, the laser transceiver node 120 can also serve alarge number of subscribers while reducing the number of connections atboth the data service hub 110 and the laser transceiver node 120 itself.

[0090] The laser transceiver node 120 also lends itself to efficientupgrading that can be performed entirely on the network side or dataservice hub 110 side. That is, upgrades to the hardware forming thelaser transceiver node 120 can take place in locations between andwithin the data service hub 110 and the laser transceiver node 120. Thismeans that the subscriber side of the network (from distribution opticalwaveguides 150 to the subscriber optical interfaces 140) can be leftentirely in-tact during an upgrade to the laser transceiver node 120 ordata service hub 110 or both.

[0091] The following is provided as an example of an upgrade that can beemployed utilizing the principles of the present invention. In oneexemplary embodiment of the invention, the subscriber side of the lasertransceiver node 120 can service six groups of 16 subscribers each for atotal of up to 96 subscribers. Each group of 16 subscribers can share adata path of about 450 Mb/s speed. Six of these paths represents a totalspeed of 6×450=2.7 Gb/s. In the most basic form, the data communicationspath between the laser transceiver node 120 and the data service hub 110can operate at 1 Gb/s. Thus, while the data path to subscribers cansupport up to 2.7 Gb/s, the data path to the network can only support 1Gb/s. This means that not all of the subscriber bandwidth is useable.This is not normally a problem due to the statistical nature ofbandwidth usage.

[0092] An upgrade could be to increase the 1 Gb/s data path speedbetween the laser transceiver node 120 and the data service hub 110.This may be done by adding more 1 Gb/s data paths. Adding one more pathwould increase the data rate to 2 Gb/s, approaching the totalsubscriber-side data rate. A third data path would allow thenetwork-side data rate to exceed the subscriber-side data rate. In otherexemplary embodiments, the data rate on one link could rise from 1 Gb/sto 2 Gb/s then to 10 Gb/s, so when this happens, a link can be upgradedwithout adding more optical links.

[0093] The additional data paths (bandwidth) may be achieved by any ofthe methods known to those skilled in the art. It may be accomplished byusing a plurality of optical waveguide transceivers 430 operating over aplurality of optical waveguides, or they can operate over one opticalwaveguide at a plurality of wavelengths, or it may be that higher speedoptical waveguide transceivers 430 could be used as shown above. Thus,by upgrading the laser transceiver node 120 and the data service hub 110to operate with more than a single 1 Gb/s link, a system upgrade iseffected without having to make changes at the subscribers' premises.

[0094] Referring now to FIG. 5, this Figure is a functional blockdiagram illustrating an optical tap 130 connected to a subscriberoptical interface 140 by a single optical waveguide 150 according to oneexemplary embodiment of the present invention. The optical tap 130 cancomprise a combined signal input/output port that is connected toanother distribution optical waveguide that is connected to a lasertransceiver node 120. As noted above, the optical tap 130 can comprisean optical splitter 510 that can be a 4-way or 8-way optical splitter.Other optical taps having fewer or more than 4-way or 8-way splits arenot beyond the scope of the present invention. The optical tap candivide downstream optical signals to serve respective subscriber opticalinterfaces 140. In the exemplary embodiment in which the optical tap 130comprises a 4-way optical tap, such an optical tap can be of thepass-through type, meaning that a portion of the downstream opticalsignals is extracted or divided to serve a 4-way splitter containedtherein, while the rest of the optical energy is passed furtherdownstream to other distribution optical waveguides 150.

[0095] The optical tap 130 is an efficient coupler that can communicateoptical signals between the laser transceiver node 120 and a respectivesubscriber optical interface 140. Optical taps 130 can be cascaded, orthey can be connected in a star architecture from the laser transceivernode 120. As discussed above, the optical tap 130 can also route signalsto other optical taps that are downstream relative to a respectiveoptical tap 130.

[0096] The optical tap 130 can also connect to a limited or small numberof optical waveguides so that high concentrations of optical waveguidesare not present at any particular laser transceiver node 120. In otherwords, in one exemplary embodiment, the optical tap can connect to alimited number of optical waveguides 150 at a point remote from thelaser transceiver node 120 so that high concentrations of opticalwaveguides 150 at a laser transceiver node can be avoided. However,those skilled in the art will appreciate that the optical tap 130 can beincorporated within the laser transceiver node 120 as will be discussedin further detail below with respect to another exemplary embodiment ofthe laser transceiver node 120 as illustrated in FIG. 12.

[0097] The subscriber optical interface 140 functions to convertdownstream optical signals received from the optical tap 130 into theelectrical domain that can be processed with appropriate communicationdevices. The subscriber optical interface 140 further functions toconvert upstream electrical signals into upstream optical signals thatcan be propagated along a distribution optical waveguide 150 to theoptical tap 130. The subscriber optical interface 140 can comprise anoptical diplexer 515 that divides the downstream optical signalsreceived from the distribution optical waveguide 150 between abidirectional optical signal splitter 520 and an analog optical receiver525. The optical diplexer 515 can receive upstream optical signalsgenerated by a digital optical transmitter 530. The digital opticaltransmitter 530 converts electrical binary/digital signals to opticalform so that the optical signals can be transmitted back to the dataservice hub 110. Conversely, the digital optical receiver 540 convertsoptical signals into electrical binary/digital signals so that theelectrical signals can be handled by processor 550.

[0098] The present invention can propagate the optical signals atvarious wavelengths. However, the wavelength regions discussed arepractical and are only illustrative of exemplary embodiments. Thoseskilled in the art will appreciate that other wavelengths that areeither higher or lower than or between the 1310 and 1550 nm wavelengthregions are not beyond the scope of the present invention.

[0099] The analog optical receiver 525 can convert the downstreambroadcast optical video signals into modulated RF television signalsthat are propagated out of the modulated RF unidirectional signal output535. The modulated RF unidirectional signal output 535 can feed to RFreceivers such as television sets (not shown) or radios (not shown). Theanalog optical receiver 525 can process analog modulated RF transmissionas well as digitally modulated RF transmissions for digital TVapplications.

[0100] The bi-directional optical signal splitter 520 can propagatecombined optical signals in their respective directions. That is,downstream optical signals entering the bi-directional optical splitter520 from the optical the optical diplexer 515, are propagated to thedigital optical receiver 540. Upstream optical signals entering it fromthe digital optical transmitter 530 are sent to optical diplexer 515 andthen to optical tap 130. The bi-directional optical signal splitter 520is connected to a digital optical receiver 540 that converts downstreamdata optical signals into the electrical domain. Meanwhile thebi-directional optical signal splitter 520 is also connected to adigital optical transmitter 530 that converts upstream electricalsignals into the optical domain.

[0101] The digital optical receiver 540 can comprise one or morephotoreceptors or photodiodes that convert optical signals into theelectrical domain. The digital optical transmitter can comprise one ormore lasers such as the Fabry-Perot (F-P) Lasers, distributed feedbacklasers, and Vertical Cavity Surface Emitting Lasers (VCSELs).

[0102] The digital optical receiver 540 and digital optical transmitter530 are connected to a processor 550 that selects data intended for theinstant subscriber optical interface 140 based upon an embedded address.The data handled by the processor 550 can comprise one or more oftelephony and data services such as an Internet service. The processor550 is connected to a telephone input/output 555 that can comprise ananalog interface. The processor 550 is also connected to a datainterface 560 that can provide a link to computer devices, set topboxes, ISDN phones, and other like devices. Alternatively, the datainterface 560 can comprise an interface to a Voice over InternetProtocol (VoIP) telephone or Ethernet telephone. The data interface 560can comprise one of Ethernet's (10BaseT, 100BaseT, Gigabit) interface,HPNA interface, a universal serial bus (USB) an IEEE1394 interface, anADSL interface, and other like interfaces.

[0103] Referring now to FIG. 6, this figure is a functional blockdiagram illustrating an exemplary data service hub 110B according to analternative exemplary embodiment of the present invention where upstreamoptical signals and downstream optical signals are propagated alongseparate optical waveguides such as the second optical waveguide 170 andthe third optical waveguide 180 discussed above with respect to FIG. 1.In other words, in this exemplary embodiment, the second opticalwaveguide 170 is designed to carry only downstream optical signals whilethe third optical waveguide 180 is designed to carry only upstreamoptical signals from the laser transceiver node 120.

[0104] The exemplary data service hub 110B further comprises adownstream optical signal output port 605 that is coupled to the secondoptical waveguide 170. The data service hub 110B further comprises anupstream optical signal input port that is coupled to the third opticalwaveguide 180. With the exemplary data service hub 110B separate opticalwaveguides 180 and 170 carry the respective upstream and downstreamoptical transmissions. With this exemplary embodiment, power can beconserved since additional components that were previously used tocombine and separate the upstream and downstream optical signals areeliminated.

[0105] This exemplary embodiment of the data service hub 110B canfurther reduce distance limitations due to power loss and cross talk. Inother words, at each end of an optical transmitter, which is supplying alot of optical power compared with the received power, can createinterference at the receiver due to incomplete isolation between theupstream and downstream optical signal directions. By utilizing separateoptical waveguides for the upstream and downstream optical signals, thisinterference can be substantially reduced or eliminated.

[0106] Referring now to FIG. 7, this Figure illustrates a functionalblock diagram of an exemplary outdoor laser transceiver node 120B thatcan accept upstream and downstream optical signals that are propagatedalong separate optical waveguides in addition to unidirectional signalsthat can be mixed with downstream optical signals. In other words, thelaser transceiver node 120B can be coupled to the exemplary data servicehub 110B illustrated in FIG. 6.

[0107] The laser transceiver node 120B can comprise a downstream opticalsignal input port 705 that is coupled to the second optical waveguide170 as illustrated in FIG. 1. The downstream optical signal input port705 is coupled to an optical receiver 710 that converts the downstreamoptical signals into the electrical domain. The optical receiver 710 inturn, feeds the electrical signals to the optical tap routing device435.

[0108] The laser transceiver node 120B of FIG. 7 can further comprise anoptical transmitter 720 that converts electrical signals received fromthe optical tap routing device 435 into the optical domain. The opticalsignals generated by the optical transmitter 720 are fed to an upstreamoptical signal output port 715. The upstream optical signal output port715 is coupled to the third optical waveguide 180 as illustrated inFIG. 1. Compared to the exemplary laser transceiver node 120Aillustrated in FIG. 4, the bi-directional splitter 360 has been replacedwith a second diplexer 420 ₂. The optical transmitter 325 generatesoptical signals of a wavelength that is higher than the upstream opticalsignals produced by a respective subscriber optical interface 140. Forexample, in one exemplary embodiment, the optical transmitter 325 canproduce optical signals having wavelengths between 1410 and 1490 nmwhile the upstream optical signals remain at the 1310 nm wavelengthregion.

[0109] As noted above, those skilled in the art will appreciate that thewavelengths discussed are only illustrative in nature. In somescenarios, it may be possible to use communication windows at 1310 and1550 nm in different ways without departing from the scope and spirit ofthe present invention. Further, the present invention is not limited tothe wavelength regions discussed above. Those skilled in the art willappreciate that smaller or larger wavelengths for the optical signalsare not beyond the scope and spirit of the present invention.

[0110] Because of the difference in wavelength regions between theupstream and downstream optical signals, the additional diplexer 420 canbe substituted for the previous bi-directional splitter 360 (illustratedin the exemplary embodiment of FIG. 4). The additional or substituteddiplexer 420 does not exhibit the same loss as the previousbi-directional splitter 360 that is used in the exemplary embodiment ofFIG. 4. This substitution of the bi-directional splitter 360 with theadditional diplexer 420 can also be applied to the subscriber opticalinterface 140. That is, when the upstream and downstream optical signalsare operating at respective different wavelength regions, thebi-directional optical signal splitter 520 of the subscriber opticalinterface 140 can be substituted with a diplexer 420. The substitutionof the bidirectional splitter 360 with the diplexer 420 can reduce theoptical loss between the laser transceiver node 120 and the subscriberoptical interface 140.

[0111] Alternatively, if the laser transceiver node 120 is using thesame wavelengths for the upstream and downstream optical signals, theoptical interface 140 uses the bidirectional optical signal splitter 520with a corresponding loss in optical power as illustrated in FIG. 5.Those skilled in the art will appreciate that various othersubstitutions for the components of the laser transceiver node 120 canbe made without departing from the scope and spirit of the presentinvention.

[0112] Referring now to FIG. 8, this Figure illustrates anotherexemplary outdoor, laser transceiver node 120C that can accept opticalsignals propagating from separate upstream and downstream opticalwaveguides in addition to multiple optical waveguides that propagateunidirectional signals. In this exemplary embodiment, the lasertransceiver node 120C of FIG. 8 can comprise multiple unidirectionalsignal input ports 805 that are coupled to a plurality of first opticalwaveguides 160. In this exemplary embodiment, compared to the lasertransceiver node 120A of FIG. 4 and laser transceiver node 120B of FIG.7, the amplifier 410 has been removed from the laser transceiver node120C as illustrated in FIG. 8. The amplifier 410 is taken out of thelaser transceiver node 120C and placed in the data service hub 110.

[0113] The optical signals propagating from the multiple first opticalwaveguides 160 are combined with the upstream and downstream opticalsignals originating from the second set of diplexers 420 ₂ using thefirst set of diplexers 420 ₁. This design to remove the amplifier 410(that typically comprises an Erbium Doped Fiber Amplifier—EDFA) from thelaser transceiver node 120C of FIG. 8 to the data service hub 110 and toinclude multiple first optical waveguides 160 feeding into the lasertransceiver node 120C, may be made on the basis of economics and opticalwaveguide availability.

[0114]FIG. 9 illustrates another exemplary embodiment of a data servicehub 110D in which unidirectional signals such as video or RF signals arecombined with downstream optical signals. In this exemplary embodiment,the data service hub 110D further comprises a splitter 415 that feedsthe broadcast video optical signals to respective diplexers 420. Therespective diplexers 420 combine the broadcast video optical signalswith the downstream data optical signals produced by respective opticaltransmitters 325. In this way, the first optical waveguide 160 asillustrated in FIG. 1 can be eliminated since the broadcast videooptical signals are combined with the downstream data optical signalsalong the second optical waveguide 170.

[0115]FIG. 10 illustrates another exemplary laser transceiver node 120Dthat can be coupled to the data service hub 110D as illustrated in FIG.9. In this exemplary embodiment, the laser transceiver node 120Dcomprises a combined downstream optical signal input 1005 that iscoupled to a second optical waveguide 160 that provides a combineddownstream optical signal comprising broadcast video services and dataservice. The laser transceiver node 120D further comprises a diplexer420 that feeds the broadcast video or RF signals to an amplifier 410.The broadcast video or RF optical signals are then sent to a splitter415 which then sends the optical signals to the first set of diplexers420 ₁. The combination of the data service hub 110D as illustrated inFIG. 9 and the laser transceiver node 120D as illustrated in FIG. 10conserves optical waveguides between these two devices.

[0116] As noted above, in another exemplary embodiment, it may bepossible to use only a single fiber (not shown) to operatively link adata service hub 110 and a laser transceiver node 120. In such anexemplary embodiment, different wavelengths could be used to propagateupstream and downstream optical signals.

[0117]FIG. 11 is a functional block diagram illustrating anotherexemplary outdoor laser transceiver node 120E that employs dualtransceivers between tap multiplexers 440 and respective groups ofsubscribers. In this embodiment the downstream optical signalsoriginating from each respective tap multiplexer 440 are splitimmediately after the tap multiplexer 440. In this exemplary embodiment,each optical transmitter 325 is designed to service only eightsubscribers as opposed to sixteen subscribers of other embodiments. Buteach tap multiplexer 440 typically services sixteen or fewersubscribers.

[0118] In this way, the splitting loss attributed to the optical taps130 can be substantially reduced. For example, in other exemplaryembodiments that do not split the downstream optical signals immediatelyafter the tap multiplexer 440, such embodiments are designed to servicesixteen or fewer subscribers with a corresponding theoretical splittingloss of approximately 14 dB (including an allowance for losses). Withthe current exemplary embodiment that services eight or fewersubscribers, the theoretical splitting loss is reduced to approximately10.5 dB.

[0119] In laser transceiver node 120E, the optical receivers 370 cannotbe paralleled because at all times one receiver 370 or the other isreceiving signals from respective subscribers, while the other receiver370 is not receiving signals. The receiver 370 not receiving anyupstream optical signals could output noise which would interfere withreception from the receiver 370 receiving upstream optical signals.Therefore, a switch 1105 can be employed to select the optical receiver370 that is currently receiving an upstream optical signal. The tapmultiplexer can control the switch 1105 since it knows which opticalreceiver 370 should be receiving upstream optical signals at any givenmoment of time.

[0120]FIG. 12 is a functional block diagram illustrating anotherexemplary outdoor laser transceiver node 120F that includes optical taps130 disposed within the laser transceiver node 120F itself. In thisarchitecture, optical waveguides 150 from each subscriber opticalinterface 140 can be connected to the laser transceiver node 120F.Typically, the number of optical waveguides 150 that are connected tothe laser transceiver node 120F is such that two laser transceiver nodes150 are needed to support the number of optical waveguides 150. But whenless than a maximum number of subscribers exist, one laser transceivernode 120F can be used to service the existing service base. When theservice base expands to a number requiring an additional lasertransceiver node 120, the additional laser transceiver nodes can beadded.

[0121] By placing the optical taps 130 within the laser transceiver node120F, two or more laser transceiver nodes 120F can be co-located withone another for the reason discussed above. In other words, thisexemplary embodiment enables two or more laser transceiver nodes 120F tobe placed in close proximity to one another. Such placement of lasertransceiver nodes 120F can conserve power and result in significant costsavings. Furthermore, with such a co-location design, future expansionof the optical architecture 100 can easily be obtained. That is, onelaser transceiver nodes 120F can be installed until more subscribersjoin the optical network architecture 100 requiring the lasertransceiver node. Optical waveguides 150 can be connected to theco-located laser transceiver nodes as more subscribers join the opticalnetwork architecture 100.

[0122] Referring now to FIG. 13, this figure illustrates an exemplarymethod for processing unidirectional and bidirectional optical signalswith a laser transceiver node 120 of the present invention. Basically,FIG. 13 provides an overview of the processing performed by the lasertransceiver node 120.

[0123] Certain steps in the process described below must naturallyprecede others for the present invention to function as described.However, the present invention is not limited to the order of the stepsdescribed if such order or sequence does not alter the functionality ofthe present invention. That is, it is recognized that some steps may beperformed before or after other steps without departing from the scopeand spirit of the present invention.

[0124] Step 1305 is the first step in the exemplary laser transceivernode overview process 1300. In step 1305, downstream RF modulatedoptical signals are amplified by the amplifier 410 as illustrated inFIG. 4. As noted above, the amplifier 410 can comprise an Erbium DopedFiber Amplifier (EDFA). However, other optical amplifiers are not beyondthe scope of the present invention.

[0125] Next, in Step 1307, bandwidth between respective subscribers canbe apportioned with the optical tap routing device 435. In other words,the optical tap routing device 435 can adjust a subscriber's bandwidthin accordance with a subscription or on an as-needed basis. The opticaltap routing device 435 can offer a particular subscriber or groups ofsubscribers bandwidth in units of 1, 2, 5, 10, 20, 50, 100, 200, and 450Mb/s.

[0126] In Step 1310, the downstream RF modulated optical signals arecombined with the downstream optical signals originating from the tapmultiplexers 440. The combining of the downstream optical signals canoccur in diplexers 420. Subsequently, in Step 1315, the combineddownstream optical signals are propagated along the distribution opticalwaveguides 150 to respective assigned groups of optical taps 200.

[0127] In Step 1320, upstream optical signals are received by opticalreceivers 370 and then converted to upstream electrical signals. Theupstream electrical signals are sent to respective tap multiplexers 440.Electrical signals received from respective tap multiplexers 440 arecombined in the optical tap routing device 435 according to Step 1325.Also in Step 1325, the upstream electrical signals from the optical taprouting device 435 can be converted into the optical domain with eitheran optical waveguide transceiver 430 or an optical transmitter 720. InStep 1330, the upstream optical signals are propagated towards the dataservice hub 110 via a bi-directional optical waveguide 170 or adedicated upstream optical waveguide 180.

[0128] Referring now to FIG. 14, this figure illustrates a logic flowdiagram of an exemplary process for handling downstream optical signalswith a laser transceiver node 120 according to the present invention.More specifically, the logic flow diagram of FIG. 14 illustrates anexemplary method for communicating optical signals from a data serviceprovider 110 to at least one subscriber.

[0129] As noted above, certain steps in the process described below mustnaturally proceed others for the present invention to function asdescribed. However, the present invention is not limited to the order ofsteps described if such order or sequence does not alter thefunctionality of the present invention. That is, it is recognized thatsome steps may be performed before or after other steps withoutdeparting from the scope and spirit of the present invention.

[0130] Step 1405 is the first step in the exemplary process 1400 forcommunicating optical signals from a data service provider to at leastone subscriber. In step 1405, downstream optical signals are received atthe laser transceiver node 120. For example, downstream optical signalscan be received at the unidirectional optical signal input port 405 asillustrated in FIG. 4. Further, downstream optical signals can also bereceived at the bi-directional optical signal input/output port 425 alsoillustrated in FIG. 4.

[0131] Next in Step 1410, the downstream optical signals can beconverted to the electrical domain. In other words, the downstreamoptical signals received at the bi-directional output signalinput/output port 425 can be converted into the electrical domain withan optical waveguide transceiver 430. As noted above, the opticalwaveguide transceiver 430 can comprise an optical/electrical converter.Next, in Step 1415 the optical tap routing device 435 can divide theconverted electrical signals between tap multiplexers 440 that areassigned to groups of optical taps 130. In Step 1420, the downstreambandwidth can be apportioned for subscribers with the optical taprouting device 435.

[0132] In this step, the optical tap routing device 435 can apportionbandwidth to groups of subscribers based upon a subscription or basedupon a current demand. The optical tap routing device 435 can partitionthe bandwidth in units of 1, 2, 5, 10, 20, 50, 100, 200, and 450 Mb/s.However, the present invention is not limited to these increments. Otherincrements of bandwidth are not beyond the scope and spirit of thepresent invention. The optical tap routing device 435 can apportionbandwidth in this way by executing a program defining a protocol forcommunications with groups of subscribers assigned to single ports. Thesingle ports are connected to the respective tap multiplexers 440.

[0133] In Step 1425, the downstream electrical signals processed by theoptical tap routing device 435 are multiplexed with the tap multiplexers440. Subsequently, in Step 1430 the downstream electrical signals can beconverted into downstream optical signals with the optical transmitters325. As noted above, the optical transmitters 325 can comprise one ofFabry-Perot (F-P) lasers, distributed feedback lasers, and VerticalCavity Surface Emitting Lasers (VCSELs). However, as noted above, othertypes of lasers are not beyond the scope of the present invention.

[0134] In Step 1435 the unidirectional RF modulated optical signalsreceived from the first optical waveguide 160 can be split into aplurality of paths with a splitter 415. Next, in Step 1440 thedownstream paths of the RF modulated optical signals are combined withthe paths of the downstream optical signals originating from the tapmultiplexers 440.

[0135]FIG. 15 illustrates a logic flow diagram of an exemplary processfor handling upstream optical signals with an exemplary lasertransceiver node 120 according to the present invention. Morespecifically, FIG. 15 illustrates a process for communicating opticalsignals from at least one subscriber to a data service provider hub.

[0136] As noted above, certain steps in the process described below mustnaturally proceed others for the present invention to function asdescribed. However, the present invention is not limited to the order ofthe steps described if such order or sequence does not alter thefunctionality of the present invention. That is, it is recognized thatsome steps may be performed before or after other steps withoutdeparting from the scope and spirit of the present invention.

[0137] Step 1505 is the first step in the exemplary laser transceivernode upstream process 1500. In Step 1505, upstream optical signalsoriginating from subscribers to optical taps 130 are propagated alongdistribution optical waveguides 150. Next, the upstream optical signalsare converted by a optical receiver 370 in Step 1510. In Step 1515, theupstream electrical signals are combined at the optical tap routingdevice 435. Next, in Step 1520 upstream bandwidth for subscribers isapportioned with the optical tap routing device 435 similar to how thedownstream optical bandwidth is apportioned as discussed above withrespect to FIG. 14.

[0138] For the upstream optical signals, the optical tap routing device435 can employ time division multiple access (TDMA) in order to serviceor support signals originating from multiple tap multiplexers 440. Asmay be apparent to those skilled in the art, in time division multipleaccess the optical tap routing device 435 switches in time from one tapmultiplexer 440 to another tap multiplexer 440. In contrast, for thedownstream optical signals, the optical tap routing device 435 employstime division multiplexing (TDM). As is apparent to those skilled in theart, time division multiplexing occurs when the optical tap routingdevice 435 sends data to multiple tap multiplexers 440. In time divisionmultiplexing, the signal is never removed, so receiving clocks remainsynchronized.

[0139] In Step 1525, the combined upstream electrical signals areconverted to upstream optical signals with either the optical waveguidetransceiver 430 or the optical transmitter 720. Next, in Step 1530, thecombined upstream optical signals are propagated along an opticalwaveguide such as the second optical waveguide 170 or third opticalwaveguide 180 to the data service hub 110.

[0140]FIG. 16 is a logic flow diagram illustrating the processing ofunidirectional and bidirectional optical signals with an optical tap 130according to the present invention. As noted above, certain steps in theprocess described below must naturally proceed others for the presentinvention to function as described. However, the present invention isnot limited to the order of steps described if such order or sequencedoes not alter the functionality of the present invention. That is, itis recognized that some steps may be performed before or after othersteps without departing from the scope and spirit of the presentinvention.

[0141] Step 1605 is the first step in the optical tap process 1600. Step1605 diverts signals from an optical waveguide such as a distributionoptical waveguide 150 coupled to a laser transceiver node to thecombined signal input/output port 505. Next in Step 1610 downstreamoptical signals that were tapped are split with the optical splitter510. The optical splitter 510 can split the downstream optical signalsto one or more subscriber interfaces or other taps or splitters orcombination thereof via distribution optical waveguides 150. In Step1615, the downstream tap combined optical signals can be propagated toand upstream optical signal from respective subscribers can be receivedand combined with the optical splitter 510.

[0142]FIG. 17 is a logic flow diagram illustrating exemplary processingof unidirectional optical signals and bi-directional optical signalswith a subscriber optical interface 140 according to the presentinvention. As noted above, certain steps in the process described belowmust naturally proceed others for the present invention to function asdescribed. However, the present invention is not limited to the order ofsteps described if such order or sequence does not alter thefunctionality of the present invention. That is, it is recognized thatsome steps may be performed before or after other steps withoutdeparting from the scope and spirit of the present invention.

[0143] Step 1705 is the first step in the subscriber optical interfaceprocess 1700. In Step 1705, combined downstream optical signals arereceived with an optical diplexer 515. Next, in Step 1710, the RFmodulated downstream optical signals are separated from the downstreamdata optical signals originating from the tap multiplexers 440. In Step1715, the downstream RF modulated optical signals are converted todownstream electrical optical signals with an analog optical receiver525. As noted above, the analog optical receiver 525 can handle bothanalog modulated signals in addition to digitally modulated signals fordigital TV applications.

[0144] In Step 1720, the upstream electrical signals are converted tooptical signals with the digital optical transmitter 530. As notedabove, the digital optical transmitter 530 can comprise one of aFabry-Perot (F-P) laser, a distributed feedback (DFB) laser, and avertical cavity surface emitting laser (VCSEL) or other similar lasers.The upstream electrical signals can be generated from a telephoneinput/output port 555 or a data interface 560 or both (as discussedabove).

[0145] In Step 1725, downstream electrical signals emitted from thedigital optical receiver 540 are received by a processor 550. Theprocessor 550, in turn, propagates these electrical signals toappropriate output devices such as the telephone input/output port 555or data interface 560 or both. As noted above, the telephoneinput/output port 555 or the data interface 560 or both can generateupstream electrical signals that are sent to the processor 550 and thenconverted into the optical domain with the digital optical transmitter530.

[0146] Those skilled in the art will appreciate that the optical networkarchitecture 100 of the present invention can provide at least one ofvideo, telephone, and computer communication services via the opticalsignals. Also, those skilled in the art will appreciate that the videolayer comprising the RF modulated signals can be removed from theexemplary optical network architecture 100 without departing from thescope and spirit of the present invention.

[0147] With the present invention, an all fiber optical network andmethod that can propagate the same bit rate downstream and upstreamto/from a network subscriber are provided. Further, the presentinvention provides an optical network system and method that can servicea large number of subscribers while reducing the number of connectionsat the data service hub.

[0148] The present invention also provides an active signal source thatcan be disposed between a data service hub and a subscriber and that canbe designed to withstand outdoor environmental conditions. The presentinvention can also be designed to hang on a strand or fit in a pedestalsimilar to conventional cable TV equipment that is placed within a lastmile of a communications network. The system and method of the presentinvention can receive at least one Gigabit or faster Ethernetcommunications in optical form from a data service hub and partition orapportion this optical bandwidth into distribution groups of apredetermined number. The system and method of the present invention canallocate additional or reduced bandwidth based upon the demand of one ormore subscribers on an optical network. Additionally, the opticalnetwork system of the present invention lends itself to efficientupgrading that can be performed entirely on the network side. In otherwords, the optical network system allows upgrades to hardware to takeplace in locations between and within a data service hub and an activesignal source disposed between the data service hub and a subscriber.

[0149] It should be understood that the foregoing relates only toillustrate the embodiments of the present invention, and that numerouschanges may be made therein without departing from the scope and spiritof the invention as defined by the following claims.

What is claimed is:
 1. An optical network system comprising: a dataservice hub; at least one optical tap; at least one subscriber opticalinterface connected to the optical tap; a laser transceiver nodedisposed between the data service hub and the optical tap, forcommunicating optical signals between the data service hub and theoptical tap, and for apportioning bandwidth between subscribers of theoptical network system, and one or more optical waveguides connectedbetween respective optical taps and the laser transceiver node, forcarrying the upstream optical signals and the downstream opticalsignals, whereby the number of the waveguides is minimized while opticalbandwidth for subscribers is controllable by the laser transceiver nodein response to subscriber demand.
 2. The optical network system of claim1, wherein the laser transceiver node further comprises an optical taprouting device for apportioning the bandwidth between subscribers of theoptical network system.
 3. The optical network system of claim 1,wherein the laser transceiver node further comprises: at least onemultiplexer coupled to an optical tap routing device; at least oneoptical transmitter connected to the at least one multiplexer, fortransmitting downstream optical signals received from the data servicehub to at least one subscriber optical interface of the optical networksystem; and at least one optical receiver connected to each multiplexer,for receiving and converting upstream optical signals from at least onesubscriber optical interface of the optical network system.
 4. Theoptical network system of claim 1, wherein the laser transceiver nodefurther comprises at least one diplexer connected to the at least oneoptical transmitter and optical receiver, each diplexer combiningdownstream RF modulated optical signals received from the data servicehub with the downstream optical signals, each diplexer being connectedto a respective optical waveguide.
 5. The optical network system ofclaim 1, wherein the laser transceiver node accepts gigabit Ethernetoptical signals from the data service hub and partitions the Ethernetoptical signals into a predetermined number of groups.
 6. The opticalnetwork system of claim 1, wherein the laser transceiver node comprisespassive cooling devices in order to operate in a temperature rangebetween −40 degrees Celsius to 60 degrees Celsius.
 7. The opticalnetwork system of claim 1, wherein the laser transceiver node ismountable on a strand in an overhead plant environment.
 8. The opticalnetwork system of claim 1, wherein the laser transceiver node is housedwithin a pedestal in an underground plant environment.
 9. The opticalnetwork system of claim 1, wherein a distance between the lasertransceiver node and the data service hub comprises a range between zeroand eighty kilometers.
 10. The optical network system of claim 1,wherein the laser transceiver node comprises at least one opticaltransmitter, each optical transmitter comprises one of a Fabry-Perotlaser, a distributed feedback laser, and a vertical cavity surfaceemitting laser (VCSEL).
 11. The optical network system of claim 1,wherein the laser transceiver node further comprises an optical taprouting device that allocates additional or reduced optical bandwidth toat least one subscriber optical interface relative to other subscriberoptical interfaces in the optical network system.
 12. The opticalnetwork system of claim 1, wherein the laser transceiver node comprisesan optical tap routing device that manages upstream and downstreamoptical signal protocols.
 13. The optical network system of claim 11,wherein one of the protocols comprises a time division multiple accessprotocol.
 14. The optical network system of claim 1, wherein data bitrates for the upstream and downstream optical signals are substantiallysymmetrical.
 15. The optical network system of claim 1, wherein eachoptical waveguide handles data rates of at least 450 Mb/s.
 16. Theoptical network system of claim 1, wherein each optical tap comprises atleast one optical splitter.
 17. The optical network system of claim 1,wherein one of the optical taps servicing a particular group ofsubscriber optical interfaces is connected to another optical tap. 18.The optical network system of claim 1, wherein each optical tappropagates upstream and downstream optical signals in addition todownstream RF modulated optical signals.
 19. The optical network systemof claim 1, wherein each subscriber optical interface comprises ananalog optical receiver, a digital optical receiver, and a digitaloptical transmitter.
 20. The optical network system of claim 1, whereinthe optical waveguides are a first set of optical waveguides, theoptical network system further comprising a second set of opticalwaveguides disposed between the data service hub and laser transceivernode, the second set comprising a first waveguide for carrying upstreamoptical signals to the data service hub, and a second optical waveguidefor carrying downstream optical signals to the laser transceiver node.21. An optical network system comprising: a data service hub; at leastone optical tap; at least one subscriber optical interface connected tothe optical tap; a laser transceiver node disposed between the dataservice hub and the at least one subscriber optical interface, forcommunicating optical signals between the data service hub and theoptical tap, and for apportioning bandwidth between subscribers of theoptical network system, the optical tap being disposed within the lasertransceiver node, and one or more optical waveguides connected betweenrespective optical taps and the laser transceiver node, for carrying theupstream optical signals and the downstream optical signals, whereby thenumber of the waveguides is minimized while optical bandwidth forsubscribers is controllable by the laser transceiver node in response tosubscriber demand.
 22. The optical network system of claim 21, whereineach optical tap comprises an optical splitter.
 23. The optical networksystem of claim 21, wherein one of the optical taps servicing aparticular group of subscriber optical interfaces is connected toanother optical tap.
 24. A method for communicating optical signals froma data service provider to at least one subscriber comprising the stepsof: receiving downstream optical signals in a laser transceiver nodefrom the service provider; dividing the downstream signals betweenpreassigned multiplexers in the laser transceiver node; apportioningbandwidth between subscribers in the laser transceiver node;multiplexing the downstream signals at the preassigned multiplexers; andpropagating respective combined downstream optical signals to at leastone subscriber via at least one optical tap along at least one opticalwaveguide.
 25. The method of claim 24, further comprising the step ofassigning subscribers to respective individual multiplexers.
 26. Themethod of claim 24, further comprising the steps of: receivingdownstream RF modulated optical signals from the service provider; andcombining downstream optical signals with the downstream RF modulatedoptical signals.
 27. The method of claim 24, wherein the step ofreceiving downstream optical signals further comprises the substep ofreceiving at least one gigabit or faster Ethernet optical signals fromthe data service provider.
 28. The method of claim 24, furthercomprising the step of operating the laser transceiver node between −40degrees Celsius and 60 degrees Celsius with passive temperature coolingdevices.
 29. The method of claim 24, further comprising the step ofmounting the laser transceiver node to a strand in an overhead plantenvironment.
 30. The method of claim 24, further comprising the step ofhousing the laser transceiver node within a pedestal in an undergroundplant environment.
 31. The method of claim 24, further comprising thestep of providing one of video, telephone, and internet services via theoptical signals.
 32. The method of claim 24, further comprising thesteps of: splitting combined downstream optical signals with at leastone optical tap; and propagating the split downstream optical signals toat least one subscriber along at least one optical waveguide.
 33. Themethod of claim 24, further comprising the step of connecting betweenone and sixteen subscribers to a respective optical tap.
 34. The methodof claim 24, further comprising the step of feeding one optical tap withoptical signals from another optical tap.
 35. The method of claim 24,further comprising the step of servicing between one and sixteensubscribers with the at least one optical waveguide.
 36. The method ofclaim 24, wherein the step of converting downstream electrical signalsfurther comprises modulating at least one of Fabry-Perot lasers,distributed feedback lasers, and vertical cavity surface emitting lasers(VCSELs) to generate downstream optical signals.
 37. The method of claim24, wherein the step of apportioning bandwidth further comprises thestep of allocating additional or reduced optical bandwidth for at leastone particular subscriber optical interface relative to other subscriberoptical interfaces in the optical network system.
 38. The method ofclaim 24, wherein the step of dividing the downstream electrical signalsfurther comprises the substep of using a time division multiplexprotocol to divide the downstream electrical signals between preassignedmultiplexers.
 39. The method of claim 24, further comprising the step ofmaintaining substantially symmetrical data bit rates between theupstream optical signals and the downstream optical signals.
 40. Themethod of claim 22, further comprising the step of propagating theoptical signals at data rates of at least 450 Mb/s.
 41. A method forcommunicating optical signals from at least one subscriber to a dataservice provider comprising the steps of: propagating upstream opticalsignals originating from at least one subscriber to at least one opticaltap; receiving upstream optical signals at a laser transceiver node fromthe at least one optical tap; converting the upstream optical signals toelectrical signals at the laser transceiver node; combining upstreamelectrical signals in the laser transceiver node; apportioning bandwidthfor at least one subscriber in the laser transceiver node; convertingthe combined upstream electrical signals into optical signals; andpropagating the combined upstream optical signals to the data serviceprovider along at least one optical waveguide.
 42. The method of claim41, further comprising the step of operating the laser transceiver nodebetween −40 degrees Celsius and 60 degrees Celsius with passivetemperature cooling devices.
 43. The method of claim 41, furthercomprising the step of mounting the laser transceiver node to a strandin an overhead plant environment.
 44. The method of claim 41, furthercomprising the step of housing the laser transceiver node within apedestal in an underground plant environment.
 45. The method of claim41, further comprising the step of providing one of video, telephone,and internet services via the optical signals.
 46. The method of claim41, further comprising the step of combining respective upstream opticalsignals originating from a plurality of subscribers with at least oneoptical tap.
 47. The method of claim 41, further comprising the step ofconnecting between one and sixteen subscribers to a respective opticaltap.
 48. The method of claim 41, further comprising the step ofpositioning the laser transceiver node closer to the optical tapsrelative to the data service provider.
 49. The method of claim 41,further comprising the step of feeding one optical tap with opticalsignals from another optical tap.
 50. The method of claim 41, furthercomprising the step of servicing between one and sixteen subscriberswith single optical waveguides connected to respective individualmultiplexers.
 51. The method of claim 41, further comprising the step ofmaintaining substantially symmetrical data bit rates between thedownstream optical signals and the upstream optical signals.
 52. Themethod of claim 41, further comprising the step of propagating theoptical signals at data rates of at least 450 Mb/s.